Xerophyte

Central Spines

usually 1 rather larger.

Flowers

At apex, large, lemon-yellow 7-12 cm broad, inner perianth segments broadly oblong, with a broad, more or less serrated apex, tube short woolly, scale on ovary, dark and very narrow.

Forma Aurea

The schizochromic form (Astrophytum ornatum f. aureaSN|3660]]SN|12947]]) has pale yellow stems due to the absence (or reduced production) of chlorophyll pigments

Ribs

It has 5 to 10 (generally 8) straight or frequently spiralling, rather prominent, strongly compressed, more or less sinuate and crenate .

Stem

The stem is solitary, globose when young, cylindric with age, but much smaller and thinner than the standard green form and rarely more than 10 cm tall, pale to dark yellow, with more or less dense white woolly flakes in bands forming an ornate pattern.

Radial Spines

5-11 , up to 2 cm long usually straight, subulated or ± laterally compressed, amber yellow, later brown and finally grey.

Areoles

1 to 2 cm apart, at first yellowish-white felted, later grabrescent.